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Be a shame to waste all the good material in banked oval demo derby anyway

Seriously though, what is the life expectancy of one of those chassis, 1 race, maybe 2?? Maybe thats why racers get away with sins in welding process that would never last in other avenues. I have co-workers that have come from GM and Ford's engineering group, and they all aggree that the performance end of those companys can teach a lot about performance, but little about lifespan.

-Aaron

A lot more than that. And you can buy retired NASCAR chassis for personal use for pretty reasonable prices and run them as long as you want.

I`ve been around dirt track racing all my life and have welded on many chassis ,big block modified are DOM ,sprinters are chrome moly and even racing karts are chrome moly. i`m very surprised

DOM is also Mild Steel. The difference from DOM to ERW is DOM stands for draw over madrel were as Electro resistance welding ( think I got that out right). DOM uses the same process to be formed as 4130 chromoly hence the reason for the steep price increase from it to the ERW steel. ERW steel starts off as flat strap and is them formed then pressed together and squeezed together then hit with some power to get it to stick.

Now why use Mild steel instead of moly. One you have a weight rule so why run a lite weight car when you then have to bolt on so much lead. Mild steel can be just as stong as chromoly only draw back is you have to use upwards of 30 percent more wall thickness to get it there. Second I know of is the response of mild steel. It is more forgiving as far as spring back. Now to not get in to some great detail but can you imagine a sprint car that has to do 200 laps the drivers would be wore out.

The main rails and cage can last a season or more. The front and back halfs get repaired/replaced frequently.

Wow that is longer then I expected for the cage and rails. I had a feeling the front and rear clips were changed often. Friends of mine that race lower levels at the Milwaukee Mile and such go through them quite frequently.
Thanks for the correction!!

Second I know of is the response of mild steel. It is more forgiving as far as spring back. Now to not get in to some great detail but can you imagine a sprint car that has to do 200 laps the drivers would be wore out.

Wow, the NASCAR chassis is a 'micro suspension'. Putting the driver in a chrome moly chassis would be like dropping him in a paint mixer. As many have said before me, I learn something (cool) every day.

Wow that is longer then I expected for the cage and rails. I had a feeling the front and rear clips were changed often. Friends of mine that race lower levels at the Milwaukee Mile and such go through them quite frequently.
Thanks for the correction!!

-Aaron

If you don't wreck em, you don't replace em. I ran one chassis for almost nine years on the short tracks with only minor modifications or updates through the years.

If necessity is the Mother of Invention, I must be the Father of Desperation!

DOM is also Mild Steel. The difference from DOM to ERW is DOM stands for draw over madrel were as Electro resistance welding ( think I got that out right). DOM uses the same process to be formed as 4130 chromoly hence the reason for the steep price increase from it to the ERW steel. ERW steel starts off as flat strap and is them formed then pressed together and squeezed together then hit with some power to get it to stick.

Now why use Mild steel instead of moly. One you have a weight rule so why run a lite weight car when you then have to bolt on so much lead. Mild steel can be just as stong as chromoly only draw back is you have to use upwards of 30 percent more wall thickness to get it there. Second I know of is the response of mild steel. It is more forgiving as far as spring back. Now to not get in to some great detail but can you imagine a sprint car that has to do 200 laps the drivers would be wore out.

Only benefit to a lightweight frame/cage is to allow more freedom in weight placement? That's the only benefit I can see, provided there isn't enough freedom with a steel cage/frame.

DOM is also Mild Steel. The difference from DOM to ERW is DOM stands for draw over madrel were as Electro resistance welding ( think I got that out right). DOM uses the same process to be formed as 4130 chromoly hence the reason for the steep price increase from it to the ERW steel. ERW steel starts off as flat strap and is them formed then pressed together and squeezed together then hit with some power to get it to stick.

Now why use Mild steel instead of moly. One you have a weight rule so why run a lite weight car when you then have to bolt on so much lead. Mild steel can be just as stong as chromoly only draw back is you have to use upwards of 30 percent more wall thickness to get it there. Second I know of is the response of mild steel. It is more forgiving as far as spring back. Now to not get in to some great detail but can you imagine a sprint car that has to do 200 laps the drivers would be wore out.

DOM is ERW. The difference between the two is DOM has been drawn over a mandrel but up to that point they are both formed and resistance welded in the same ways. ERW and DOM are both ASTM classification A-513. DOM is most often A-513 type 5 with type 5 meaning "drawn over mandrel". 4130 can be A-513 type 5 too, but it's most often A-519 which is true seamless tube meaning it is drawn into a hollow round by piercing solid stock. Mild steel can be A-519 as well, but that's not as common as finding it as DOM.

Also, mild steel is not more "forgiving" as far as "spring back". While spring back is not a technical term, 4130 as a material will deflect farther than mild steel (such as 1010, 1018, 1020, etc.) and still return to original shape.

Also, if 4130 was subbed for mild steel and wall thicknesses lessened to maintain the same amount of yield strength the 4130 chassis would be LESS stiff than the mild steel chassis which would have more material and thus be the reason the mild steel chassis is stiffer. This is all covered heavily in old threads.

Aaron,
NASCAR chassis last a looong time if you don't wad 'em up too bad. They make it years of racing and beyond often being recycled to the lower classes!